In well known methods, cyclic olefin compounds each having a cyclohexene skeleton are produced via dehydration of alcohols. Typically, there are disclosed in documents a technique of producing a cyclic olefin compound via dehydration of an alcohol by the catalysis of an inorganic acid such as a concentrated sulfuric acid or phosphoric acid (see Non-patent Document 1) and techniques for producing cyclic olefin compounds via dehydration of alcohols using potassium hydrogen sulfate (KHSO4) as an acidic salt (see Patent Document 1, Non-patent Document 2, and Non-patent Document 3).
These known techniques for producing cyclic olefin compounds, however, are not always satisfactory in yield and purity of the resulting cyclic olefin compounds. Specifically, the known technique using a concentrated sulfuric acid with high acidity is likely to suffer from side reactions, and the resulting by-product compounds other than a target cyclic olefin compound reduce the yield of the target cyclic olefin compound. In the other known techniques using an inorganic salt of sulfuric acid, such as potassium hydrogen sulfate, or phosphoric acid, the reaction should be carried out at a higher temperature and/or for a longer duration, because these components have low acidity. Consequently, side reactions also occur to reduce the yield of the target cyclic olefin compound and to cause by-product colored components and isomer components which are very hard to be separated from the target cyclic olefin compound. In addition, an inorganic salt of sulfuric acid, such as potassium hydrogen sulfate, is very sparingly soluble in reaction materials and organic solvents, whereby the reaction should be carried out at a further higher temperature for a further longer duration, and this causes considerable side reactions. Additionally, in the known techniques, the concentration of substrate is generally low and the reducibility is considerably low.
Particularly in production of a cyclic olefin compound having two or more cyclohexene rings per molecule via intramolecular dehydration of an alicyclic alcohol having two or more hydroxylated cyclohexane rings per molecule, isomerization occurs during the reaction to form by-product isomers differing in the position of double bond and to form by-product cyclic olefin compounds in which, for example, only one of hydroxylated cyclohexane rings has been dehydrated (i.e., cyclic olefin compounds each having one or more residual hydroxylated cyclohexane rings per molecule). These isomers have properties, such as boiling point and solubility in an solvent, similar to those of the target compound, and when once formed, they are difficult to separate from the target compound and contaminate the product, thus, it is difficult to obtain the target compound with a high purity. Additionally, some of cyclic olefin compounds having one or more residual hydroxylated cyclohexane rings per molecule are sublimable and may adhere to walls of a reactor and attachments thereof to cause a blockage of the system.
This will be illustrated in further detail. By way of example, when a cyclohexyl alcohol derivative having a substituent at the 4-position is heated in the presence of a dehydration catalyst, and when the heating is conducted in a system in the coexistence of water, not only dehydration but also reverse reactions thereof (addition reactions of water) proceed to form, in addition to a target cyclic olefin, by-product two isomers differing in the position of double bond as illustrated in the following reaction formula in which R represents a substituent.

In addition, the number of isomers further increases when the substituent R has one or more hydroxylated cyclohexane rings. By way of example, when a hydrogenated biphenol represented by following Formula (1a):
is used as a starting material, six different isomers (cyclic olefin compounds) represented by following Formulae (3a) to (3f) can be formed. Specifically, five different by-products can be formed when a compound represented by Formula (3a) (bicyclohexyl-3,3′-diene; a colorless transparent liquid having a boiling point of 260° C. at 760 Torr and 140° C. at 10 Torr) is the target compound.

Dehydration of a cyclohexyl alcohol derivative having two or more hydroxylated cyclohexane rings per molecule may yield a reaction intermediate having a cyclohexene ring and a hydroxylated cyclohexane ring per molecule. Typically, dehydration of the hydrogenated biphenol as a starting material gives a by-product compound represented by following Formula (4) (a white solid (at normal temperature) having a boiling point of 380° C. at 760 Torr and 230° C. at 10 Torr). This compound is sublimable and may adhere to the inside typically of a distillation column, if provided in a reactor, and may cause a blockage of the distillation column.

On the other hand, Japanese Unexamined Patent Application Publication (JP-A) No. 2005-97274 (Patent Document 2) discloses a method of producing bicyclohexyl-3,3′-diene via intramolecular dehydration of hydrogenated biphenol in the presence of an alkali metal hydrogen sulfate such as potassium hydrogen sulfate and in the absence of a solvent, in which produced water and bicyclohexyl-3,3′-diene are immediately distilled off from the reactor to prevent side reactions and to thereby give high-purity bicyclohexyl-3,3′-diene. According to this method, however, it is difficult to render the reaction system homogeneous even at temperatures at which a reaction begins, because the starting material hydrogenated biphenol melts at around 180° C., and it is difficult to stir the reaction system until the temperature rises to around this temperature. Additionally, use of potassium hydrogen sulfate requires a corrosion-resisting apparatus typically with glass lining, because potassium hydrogen sulfate corrodes stainless steels SUS 304 and SUS 316 which are generally used as materials for chemical apparatuses (chemical plants) made of metals. However, there are few glass-lined reactors that can be heated up to such high temperatures of from 180° C. to 200° C. In addition, heat shock due to produced water may probably cause a crack or delamination of the glass lining. Thus, this method is highly susceptible to improvements in order to carry out industrially. Furthermore, the method requires a large amount of a dehydration catalyst.    [Patent Document 1] JP-A No. 2000-169399    [Patent Document 2] JP-A No. 2005-97274    [Non-patent Document 1] Org. Synth. Coll. Vol. 2, 151 (1943)    [Non-patent Document 2] J. Chem. Soc., 1950, 2725    [Non-patent Document 3] Shin Jikken Kagaku Koza (in Japanese; “Courses in Experimental Chemistry, New Ed.”) vol. 14, Syntheses and Reactions of Organic Compounds I, 119 (1978) edited by The Chemical Society of Japan